Which of the following circuit is used as a ‘Memory device’ in computers?

Rectifier
Flip Flop
Comparator
Attenuator E. None of these

The correct answer is B. Flip Flop.

A flip-flop is a type of electronic circuit that has two stable states. It can be used to store data, and is the basic building block of memory devices.

A rectifier is a device that converts alternating current (AC) to direct current (DC).

A comparator is a device that compares two signals and outputs a signal indicating which signal is greater.

An attenuator is a device that reduces the amplitude of a signal.

None of these devices are used as memory devices in computers.